Bone marrow is the spongy tissue inside some of you r bones, such as your hip and thigh bones. It contains immature cells, called stem cells. The ste m cells can develop into the red blood cells that carry oxygen through your body, the white bloo d cells that fight infections, and the platelets that help with blood clotting. If you have a bone m arrow disease, there are problems with the stem cells or how they develop. Leukemia is a cance r in which the bone marrow produces abnormal white blood cells. With aplastic anemia, t he bone marrow doesn't make red blood cells. Other diseases, such as lymphoma, can spread into t he bone marrow and affect the production of blood cells. Other causes of bone marrow disorders include your genetic makeup and environmental factors. The cell compression caused by an overgrowth of the supporting fibrous tissue network, resulting in abnormally shaped cell s and decreased numbers of cells. One cell line that becomes predominant because the cells don 't die at a normal rate. Diseases that may spread to the bone marrow, affecting cell productio n and maturation. Symptoms of bone marrow diseases vary. Treatments depend on the disorder an d how severe it is. They might involve medicines, blood transfusions or a bone marrow tran splant.